Slow Xrumer email downloading for activation?

Does anyone know why downloading activation emails in xrumer is so slow?

I have a server can post 1800/minute but then when it has to download the activation emails, it downloads them at only about 7 per second no matter what email server I use, even my own. What is causing the emails to download so slowly?

it may not be your server , it could be the activation email itself. their server taking a bit longer.. let it sit for an hour or something, and see how that works out when downloading them